FIG. 1 depicts an example configuration of a mobile network comprising femto base stations. The femto base station 1 is connected to a modem 3 which is itself connected to a landline 5. Said landline is connected to a digital subscriber line access multiplexer (DSLAM) 7 connected to a network server 9.
Such a network may be divided into multiple parts:                the local network 11 comprising the femto base station 1 and the modem 3,        the access network 13 comprising the landline 5,        the aggregation network 15 the multiplexer 7 (DSLAM),        the mobile network 17 comprising an authentication, authorization and accounting (AA) server 9.        
The local portion of the network may be owned by the operator, in which case the operator installs its base stations itself, but it might also not belong to the operator, in which case the users themselves purchase and install their own base stations, for example in their homes.
With such networks, the main problem for the operator is authenticating and locating the base stations 1 which it does not own and which are connected to the network, in order to ensure the safety of the network and to allocate the appropriate frequencies for the network to run properly.
Since the femto base station 1 is installed locally by the users, the operator must identify the femto base station 1 in order to grant it the right to access the network and to share its operating resources with said femto base station.
Additionally, the operator must locate the femto base station 1 in order to allocate the appropriate frequencies to it, and thereby to prevent possible interference with neighboring cells.
Different techniques are used in the state of the art to solve these problems.
With respect to allocating frequencies, the base stations may be equipped with GPS, which is a costly solution that does not work indoors. Neighboring frequencies may also be polled, but this increases the time it takes to start up the base station.
With respect to authentication, digital certificates may be inserted into the base station or a system with a SIM card may be used, but both of these solutions are costly.
Furthermore, another problem pertains to the confidentiality of calls. If two neighboring houses are both equipped with a base station, the user may connect either to his own base station or to his neighbor's. However, there is no way to guarantee him that his neighbor's base station has not been hacked and that his calls are being monitored. The user must therefore be able to trust the base station that is transmitting and encoding his telecommunications. Solutions found in the state of the art include spoofing detection systems and electronic padlocking in order to protect the base station's encryption keys and sensitive programs. However, these solutions are costly and do not completely eliminate the risk of hacking.